Duplex centrifugal machine



March 13, 1934. J. L. TUFTS 1,950,528

DUPLEX CENTR IFUGAL MACHI NE Filed May 21, 1932 2 Sheets-Sheet 1 A/WYM March 13, 1934. J. 1. TUFTS DUPLEX CENTRIFUGAL MACHINE Filed May 21, 1932 2 Sheets-Sheet 2 no @000 o :9 e o OOOOOOOooo o0 000 OOOOOOOoooeQae OOOO OCOOOOOOOQQQS 0 @F ,aw fd 3823000000 ooooooo i 230000000000 OOOOOco 80230000000 oooooooeoe fi v OQQOOOOOOOOOOQQ ZZZZcoOOOOOOOOOQ co 253000000000 OOOOQHK ZZSQQOQOOOOOAwOOOOOOO Patented Mar. 13, 1934 UNITED TES PATENT OFFICE 2 Claims.

This invention relates to the duplex type of centrifugal machine in which two rotating bowls are mounted at opposite ends of a single drive shaft. Such a duplex arrangement has obvious advantages in use and operation.

It is the general object of my present invention to improve the construction of such duplex centrifugal machines by balancing the two rotating bowls at opposite ends of the armature shaft of an interposed electric motor, and by so mounting the motor that vibration is absorbed and that, the entire rotating structure becomes to a substantial extent self-centering.

I have also provided means to effect a circulation of air around the motor, thereby reducing the heating thereof.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appending claims.

A preferred form of the invention is shown in the drawings, in which Fig. 1 is a plan view of my improved centrifugal machine;

Fig. 2 is a sectional front elevation, taken along the line 2-2 of Fig. 1;

Fig. 3 is a detailed sectional plan view, taken along the line 33 in Fig. 2, and

Figs. 4 and 5 are sectional end elevations, taken along the lines 4-4 and 5-5 respectively in Fig. 2.

llleferrin to the drawings, I have shown a base 10 mounted on a plurality of supports 11 which may be in the form of balls or semi-circular projections on which the machine may be readily moved around.

A motor M of a usual commercial type is mounted in a frame 12 projecting upward at the center of the base 10. The motor M is supported within the frame 12 by rings 14 of rubber or other cushion material, and these rings are preferably provided with slots or openings 15 (Figs. 4. and 5) in their upper parts.

The frame 12 is provided with an opening 17 (Fig. 5) at the bottom thereof, so that air may flow upward through the opening 17 and thereafter circulate around the casing of the motor M and escape through the openings 15, thus producing a substantial cooling efiect on the motor M.

A rotating bowl 20 is mounted at each end of the armature shaft 21 of the motor M and these bowls may be either perforate or imperforate, according to the work which is to be performed.

The bowls 2c are mounted to rotate in casing members 25, preferably formed integral with or supported on the base it. A drain pan 36 is secured to the under-side of the base 10 and is provided with outlets 31 joined to a discharge pipe 32 (Fig. 1).

The casing members 25 are provided with onset portions 35 (Figs. 1 and 3) which offset portions facilitate the circulation of air in the cas ing members 25 and are of substantial advantage where a drying effect is desired, in which case, provision for maximum air circulation would be provided.

It will be noted that the hubs 40 of the bowls 20 project through openings 41 in the end walls of the casing members 25, but that they have substantial clearance therein. Consequently the entire rotating structure, including the motor armature, the armature shaft 21 and the bowls 20, is entirely supported by bearings in the motor M, which motor in turn is entirely supported on the cushion rings 14.

Consequently when the machine is in use, all vibration is absorbed by the cushion rings 14, and furthermore in case of unbalanced loads at the two ends of the shaft 21, the entire rotating structure is free to a substantial extent to find its own center of rotation, thus running much more smoothly than when an unbalanced load is supported in rigid bearings. This provision of a yielding mounting for the motor M is accordingly a most important feature of my invention.

Having thus described my invention and the advantages thereof I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is:

1. A duplex centrifugal machine comprising a base, a self-contained electric motor having an armature shaft extended in both directions substantially beyond the ends of said motor, a frame for said motor mounted on said base, a rotating bowl mounted at each end of said armature shaft, a casing for each bowl mounted on said base, and yielding means supporting said motor and permitting the armature shaft, the rotating bowls and the loads therein to act as a unit and to substantially determine their own axis of rotation, each casing having an enlarged opening about the normal shaft axis to afiord clearance greater than running clearance therefor.

2. A duplex centrifugal machine comprising a base, a self-contained electric motor having an armature shaft extended in both directions substantially beyond the ends of said motor, a frame for said motor mounted on said base, a rotating bowl mounted at each end of said armature shaft, a casing for each bowl mounted on said base, and cushion rings interposed between said motor and frame and at each side of said frame, said rings providing air openings at the top between said motor and frame and a circumferential air channel between said rings, and said frame having an air opening at the bottom into said channel, whereby free circulation of air is provided to cool the motor.

JOHN L. TU'FTS. 

